Field of the Invention
This invention relates in general to mooring arrangements for vessels and in particular to a spread mooring arrangement for a permanently moored storage vessel to which a shuttle tanker is tied up along side during product transfer.
Description of the Prior Art
A shuttle tanker tied up beside a permanently moored storage tanker needs clearance between its hull and the anchor legs of the storage tanker.
There are many permanent mooring arrangements for storage tankers yet, a possibility exists for shuttle tanker entanglement with anchor legs of the permanently moored vessel, especially if anchor legs are secured mid-way between its stern and its bow or if anchor legs are secured mid-way between its stern and its bow or if anchor legs extend from the deck via the side of the vessel.
Identification of Objects of the Invention
It is an important objective of the invention to provide a mooring arrangement for permanently mooring a storage tanker in deep water (greater than 200 meters) which substantially prevents the possibility of entanglement of the shuttle tanker with the anchor legs of the storage tanker.
Another object of this invention is to provide a spread mooring at the bow end and the stern end of the vessel to allow large shuttle vessels to be tied up alongside the storage vessel in moderate environments for offloading of hydrocarbon product without the potential to entangle the permanently installed anchor legs of the storage vessel.
Another object of this invention is to provide a double point mooring system for large vessels to be tied up together in moderate environments for offloading product from one vessel to another while providing space on the side of the storage vessel for the securement of production risers, work over risers or control umbilicals.